Hypodensity of platelet serotonin uptake sites in posttraumatic stress disorder: associated clinical features.

We have previously reported that binding to blood platelets of paroxetine, a selective serotonin (5-HT) reuptake inhibitor which binds to 5-HT uptake sites, is decreased in patients with posttraumatic stress disorder (PTSD). Specifically, we found a lower number of platelet 3H-paroxetine binding sites (Bmax) and a lower dissociation constant (Kd) for 3H-paroxetine binding in combat veterans with PTSD compared to normal control subjects. In the current study we assessed the relationship of platelet 3H-paroxetine binding to clinical features in 41 Vietnam combat veterans with SCID-diagnosed PTSD. The results indicated that Bmax of platelet 3H-paroxetine binding was negatively correlated with both state and trait anxiety, as well as with depressive and overall PTSD symptoms. However, there was no evidence that platelet 3H-paroxetine binding differed as a function of comorbid psychiatric diagnoses including major depression, other anxiety disorders, and substance abuse in these patients.